<div xmlns:ext="http://www.extjs.com" class="body-wrap"><h1>Class <a href="source/DomHelper.html#cls-Ext.DomHelper">Ext.DomHelper</a></h1><table cellspacing="0"><tr><td class="label">Package:</td><td class="hd-info">Ext</td></tr><tr><td class="label">Defined In:</td><td class="hd-info"><a href="source/DomHelper.html#cls-Ext.DomHelper">DomHelper.js</a></td></tr><tr><td class="label">Class:</td><td class="hd-info"><a href="source/DomHelper.html#cls-Ext.DomHelper">DomHelper</a></td></tr><tr><td class="label">Extends:</td><td class="hd-info">Object</td></tr></table><div class="description"><p>The DomHelper class provides a layer of abstraction from DOM and transparently supports creating
elements via DOM or using HTML fragments. It also has the ability to create HTML fragment templates
from your DOM building code.</p>
<p><b><u>DomHelper element specification object</u></b></p>
<p>A specification object is used when creating elements. Attributes of this object
are assumed to be element attributes, except for 4 special attributes:
<div class="mdetail-params"><ul>
<li><b><tt>tag</tt></b> : <div class="sub-desc">The tag name of the element</div></li>
<li><b><tt>children</tt></b> : or <tt>cn</tt><div class="sub-desc">An array of the
same kind of element definition objects to be created and appended. These can be nested
as deep as you want.</div></li>
<li><b><tt>cls</tt></b> : <div class="sub-desc">The class attribute of the element.
This will end up being either the "class" attribute on a HTML fragment or className
for a DOM node, depending on whether DomHelper is using fragments or DOM.</div></li>
<li><b><tt>html</tt></b> : <div class="sub-desc">The innerHTML for the element</div></li>
</ul></div></p>
<p><b><u>Insertion methods</u></b></p>
<p>Commonly used insertion methods:
<div class="mdetail-params"><ul>
<li><b><tt><a href="output/Ext.DomHelper.html#Ext.DomHelper-append" ext:member="append" ext:cls="Ext.DomHelper">append</a></tt></b> : <div class="sub-desc"></div></li>
<li><b><tt><a href="output/Ext.DomHelper.html#Ext.DomHelper-insertBefore" ext:member="insertBefore" ext:cls="Ext.DomHelper">insertBefore</a></tt></b> : <div class="sub-desc"></div></li>
<li><b><tt><a href="output/Ext.DomHelper.html#Ext.DomHelper-insertAfter" ext:member="insertAfter" ext:cls="Ext.DomHelper">insertAfter</a></tt></b> : <div class="sub-desc"></div></li>
<li><b><tt><a href="output/Ext.DomHelper.html#Ext.DomHelper-overwrite" ext:member="overwrite" ext:cls="Ext.DomHelper">overwrite</a></tt></b> : <div class="sub-desc"></div></li>
<li><b><tt><a href="output/Ext.DomHelper.html#Ext.DomHelper-createTemplate" ext:member="createTemplate" ext:cls="Ext.DomHelper">createTemplate</a></tt></b> : <div class="sub-desc"></div></li>
<li><b><tt><a href="output/Ext.DomHelper.html#Ext.DomHelper-insertHtml" ext:member="insertHtml" ext:cls="Ext.DomHelper">insertHtml</a></tt></b> : <div class="sub-desc"></div></li>
</ul></div></p>
<p><b><u>Example</u></b></p>
<p>This is an example, where an unordered list with 3 children items is appended to an existing
element with id <tt>'my-div'</tt>:<br>
 <pre><code><b>var</b> dh = Ext.DomHelper; <i>// create shorthand alias</i>
<i>// specification object</i>
<b>var</b> spec = {
    id: <em>'my-ul'</em>,
    tag: <em>'ul'</em>,
    cls: <em>'my-list'</em>,
    <i>// append children after creating</i>
    children: [     <i>// may also specify <em>'cn'</em> instead of <em>'children'</em></i>
        {tag: <em>'li'</em>, id: <em>'item0'</em>, html: <em>'List Item 0'</em>},
        {tag: <em>'li'</em>, id: <em>'item1'</em>, html: <em>'List Item 1'</em>},
        {tag: <em>'li'</em>, id: <em>'item2'</em>, html: <em>'List Item 2'</em>}
    ]
};
<b>var</b> list = dh.append(
    <em>'my-div'</em>, <i>// the context element <em>'my-div'</em> can either be the id or the actual node</i>
    spec      <i>// the specification object</i>
);</code></pre></p>
<p>Element creation specification parameters in this class may also be passed as an Array of
specification objects. This can be used to insert multiple sibling nodes into an existing
container very efficiently. For example, to add more list items to the example above:<pre><code>dh.append(<em>'my-ul'</em>, [
    {tag: <em>'li'</em>, id: <em>'item3'</em>, html: <em>'List Item 3'</em>},
    {tag: <em>'li'</em>, id: <em>'item4'</em>, html: <em>'List Item 4'</em>}
]);</code></pre></p>
<p><b><u>Templating</u></b></p>
<p>The real power is in the built-in templating. Instead of creating or appending any elements,
<tt><a href="output/Ext.DomHelper.html#Ext.DomHelper-createTemplate" ext:member="createTemplate" ext:cls="Ext.DomHelper">createTemplate</a></tt> returns a Template object which can be used over and over to
insert new elements. Revisiting the example above, we could utilize templating this time:
<pre><code><i>// create the node</i>
<b>var</b> list = dh.append(<em>'my-div'</em>, {tag: <em>'ul'</em>, cls: <em>'my-list'</em>});
<i>// get template</i>
<b>var</b> tpl = dh.createTemplate({tag: <em>'li'</em>, id: <em>'item{0}'</em>, html: <em>'List Item {0}'</em>});

<b>for</b>(<b>var</b> i = 0; i < 5, i++){
    tpl.append(list, [i]); <i>// use template to append to the actual node</i>
}</code></pre></p>
<p>An example using a template:<pre><code><b>var</b> html = <em>'<a id=<em>"{0}"</em> href=<em>"{1}"</em> class=<em>"nav"</em>>{2}</a>'</em>;

<b>var</b> tpl = <b>new</b> Ext.DomHelper.createTemplate(html);
tpl.append(<em>'blog-roll'</em>, [<em>'link1'</em>, <em>'http:<i>//www.jackslocum.com/'</em>, <em>"Jack&#39;s Site"</em>]);</i>
tpl.append(<em>'blog-roll'</em>, [<em>'link2'</em>, <em>'http:<i>//www.dustindiaz.com/'</em>, <em>"Dustin&#39;s Site"</em>]);</i></code></pre></p>
<p>The same example using named parameters:<pre><code><b>var</b> html = <em>'<a id=<em>"{id}"</em> href=<em>"{url}"</em> class=<em>"nav"</em>>{text}</a>'</em>;

<b>var</b> tpl = <b>new</b> Ext.DomHelper.createTemplate(html);
tpl.append(<em>'blog-roll'</em>, {
    id: <em>'link1'</em>,
    url: <em>'http:<i>//www.jackslocum.com/'</em>,</i>
    text: <em>"Jack&#39;s Site"</em>
});
tpl.append(<em>'blog-roll'</em>, {
    id: <em>'link2'</em>,
    url: <em>'http:<i>//www.dustindiaz.com/'</em>,</i>
    text: <em>"Dustin&#39;s Site"</em>
});</code></pre></p>
<p><b><u>Compiling Templates</u></b></p>
<p>Templates are applied using regular expressions. The performance is great, but if
you are adding a bunch of DOM elements using the same template, you can increase
performance even further by <a href="output/Ext.Template.html#Ext.Template-compile" ext:member="compile" ext:cls="Ext.Template">"compiling"</a> the template.
The way "<a href="output/Ext.Template.html#Ext.Template-compile" ext:member="compile" ext:cls="Ext.Template">compile()</a>" works is the template is parsed and
broken up at the different variable points and a dynamic function is created and eval'ed.
The generated function performs string concatenation of these parts and the passed
variables instead of using regular expressions.
<pre><code><b>var</b> html = <em>'<a id=<em>"{id}"</em> href=<em>"{url}"</em> class=<em>"nav"</em>>{text}</a>'</em>;

<b>var</b> tpl = <b>new</b> Ext.DomHelper.createTemplate(html);
tpl.compile();

<i>//... use template like normal</i></code></pre></p>
<p><b><u>Performance Boost</u></b></p>
<p>DomHelper will transparently create HTML fragments when it can. Using HTML fragments instead
of DOM can significantly boost performance.</p>
<p>Element creation specification parameters may also be strings. If <a href="output/Ext.DomHelper.html#Ext.DomHelper-useDom" ext:member="useDom" ext:cls="Ext.DomHelper">useDom</a> is <tt>false</tt>,
then the string is used as innerHTML. If <a href="output/Ext.DomHelper.html#Ext.DomHelper-useDom" ext:member="useDom" ext:cls="Ext.DomHelper">useDom</a> is <tt>true</tt>, a string specification
results in the creation of a text node. Usage:</p>
<pre><code>Ext.DomHelper.useDom = true; <i>// force it to use DOM; reduces performance</i></code></pre><br><br><i>This class is a singleton and cannot be created directly.</i></div><div class="hr"></div><a id="Ext.DomHelper-props"></a><h2>Public Properties</h2><table cellspacing="0" class="member-table"><tbody><tr><th colspan="2" class="sig-header">Property</th><th class="msource-header">Defined By</th></tr><tr class="property-row expandable "><td class="micon"><a href="#expand" class="exi">&nbsp;</a></td><td class="sig"><a id="Ext.DomHelper-lastIndex"></a><b><a href="source/DomHelper.html#prop-Ext.DomHelper-lastIndex">lastIndex</a></b> : Object<div class="mdesc"><div class="short">Since we're using the g flag on the regex, we need to set the lastIndex.
This automatically happens on some implement...</div><div class="long">Since we're using the g flag on the regex, we need to set the lastIndex.
This automatically happens on some implementations, but not others, see:
http://stackoverflow.com/questions/2645273/javascript-regular-expression-literal-persists-between-function-calls
http://blog.stevenlevithan.com/archives/fixing-javascript-regexp</div></div></td><td class="msource">DomHelper</td></tr><tr class="property-row  "><td class="micon"><a href="#expand" class="exi">&nbsp;</a></td><td class="sig"><a id="Ext.DomHelper-useDom"></a><b><a href="source/DomHelper-more.html#prop-Ext.DomHelper-useDom">useDom</a></b> : Boolean<div class="mdesc">True to force the use of DOM instead of html fragments</div></td><td class="msource">DomHelper</td></tr></tbody></table><a id="Ext.DomHelper-methods"></a><h2>Public Methods</h2><table cellspacing="0" class="member-table"><tbody><tr><th colspan="2" class="sig-header">Method</th><th class="msource-header">Defined By</th></tr><tr class="method-row expandable "><td class="micon"><a href="#expand" class="exi">&nbsp;</a></td><td class="sig"><a id="Ext.DomHelper-applyStyles"></a><b class="method"><a href="source/DomHelper.html#method-Ext.DomHelper-applyStyles">applyStyles</a></b><span class="openparen">(&nbsp;</span><span title="Required" class="required">String/HTMLElement&nbsp;el</span><span class="comma">,&nbsp;</span><span title="Required" class="required">String/Object/Function&nbsp;styles</span><span class="closeparen">&nbsp;)</span><span class="colon">&nbsp;:&nbsp;</span><span class="return">void</span><div class="mdesc"><div class="short">Applies a style specification to an element.</div><div class="long">Applies a style specification to an element.<div class="mdetail-params"><strong>Parameters:</strong><ul><li><code>el</code> : String/HTMLElement<div class="sub-desc">The element to apply styles to</div></li><li><code>styles</code> : String/Object/Function<div class="sub-desc">A style specification string e.g. 'width:100px', or object in the form {width:'100px'}, or
a function which returns such a specification.</div></li></ul><strong>Returns:</strong><ul><li>void</li></ul></div></div></div></td><td class="msource">DomHelper</td></tr><tr class="method-row expandable "><td class="micon"><a href="#expand" class="exi">&nbsp;</a></td><td class="sig"><a id="Ext.DomHelper-createDom"></a><b class="method"><a href="source/DomHelper-more.html#method-Ext.DomHelper-createDom">createDom</a></b><span class="openparen">(&nbsp;</span><span title="Required" class="required">Object/String&nbsp;o</span><span class="closeparen">&nbsp;)</span><span class="colon">&nbsp;:&nbsp;</span><span class="return">HTMLElement</span><div class="mdesc"><div class="short">Creates new DOM element(s) without inserting them to the document.</div><div class="long">Creates new DOM element(s) without inserting them to the document.<div class="mdetail-params"><strong>Parameters:</strong><ul><li><code>o</code> : Object/String<div class="sub-desc">The DOM object spec (and children) or raw HTML blob</div></li></ul><strong>Returns:</strong><ul><li><code>HTMLElement</code><div class="sub-desc">The new uninserted node</div></li></ul></div></div></div></td><td class="msource">DomHelper</td></tr><tr class="method-row expandable "><td class="micon"><a href="#expand" class="exi">&nbsp;</a></td><td class="sig"><a id="Ext.DomHelper-createTemplate"></a><b class="method"><a href="source/DomHelper-more.html#method-Ext.DomHelper-createTemplate">createTemplate</a></b><span class="openparen">(&nbsp;</span><span title="Required" class="required">Object&nbsp;o</span><span class="closeparen">&nbsp;)</span><span class="colon">&nbsp;:&nbsp;</span><span class="return">Ext.Template</span><div class="mdesc"><div class="short">Creates a new Ext.Template from the DOM object spec.</div><div class="long">Creates a new Ext.Template from the DOM object spec.<div class="mdetail-params"><strong>Parameters:</strong><ul><li><code>o</code> : Object<div class="sub-desc">The DOM object spec (and children)</div></li></ul><strong>Returns:</strong><ul><li><code>Ext.Template</code><div class="sub-desc">The new template</div></li></ul></div></div></div></td><td class="msource">DomHelper</td></tr><tr class="method-row expandable "><td class="micon"><a href="#expand" class="exi">&nbsp;</a></td><td class="sig"><a id="Ext.DomHelper-insertHtml"></a><b class="method"><a href="source/DomHelper.html#method-Ext.DomHelper-insertHtml">insertHtml</a></b><span class="openparen">(&nbsp;</span><span title="Required" class="required">String&nbsp;where</span><span class="comma">,&nbsp;</span><span title="Required" class="required">HTMLElement&nbsp;el</span><span class="comma">,&nbsp;</span><span title="Required" class="required">String&nbsp;html</span><span class="closeparen">&nbsp;)</span><span class="colon">&nbsp;:&nbsp;</span><span class="return">HTMLElement</span><div class="mdesc"><div class="short">Inserts an HTML fragment into the DOM.</div><div class="long">Inserts an HTML fragment into the DOM.<div class="mdetail-params"><strong>Parameters:</strong><ul><li><code>where</code> : String<div class="sub-desc">Where to insert the html in relation to el - beforeBegin, afterBegin, beforeEnd, afterEnd.</div></li><li><code>el</code> : HTMLElement<div class="sub-desc">The context element</div></li><li><code>html</code> : String<div class="sub-desc">The HTML fragment</div></li></ul><strong>Returns:</strong><ul><li><code>HTMLElement</code><div class="sub-desc">The new node</div></li></ul></div></div></div></td><td class="msource">DomHelper</td></tr><tr class="method-row expandable "><td class="micon"><a href="#expand" class="exi">&nbsp;</a></td><td class="sig"><a id="Ext.DomHelper-markup"></a><b class="method"><a href="source/DomHelper.html#method-Ext.DomHelper-markup">markup</a></b><span class="openparen">(&nbsp;</span><span title="Required" class="required">Object&nbsp;o</span><span class="closeparen">&nbsp;)</span><span class="colon">&nbsp;:&nbsp;</span><span class="return">String</span><div class="mdesc"><div class="short">Returns the markup for the passed Element(s) config.</div><div class="long">Returns the markup for the passed Element(s) config.<div class="mdetail-params"><strong>Parameters:</strong><ul><li><code>o</code> : Object<div class="sub-desc">The DOM object spec (and children)</div></li></ul><strong>Returns:</strong><ul><li><code>String</code><div class="sub-desc"></div></li></ul></div></div></div></td><td class="msource">DomHelper</td></tr><tr class="method-row expandable "><td class="micon"><a href="#expand" class="exi">&nbsp;</a></td><td class="sig"><a id="Ext.DomHelper-overwrite"></a><b class="method"><a href="source/DomHelper.html#method-Ext.DomHelper-overwrite">overwrite</a></b><span class="openparen">(&nbsp;</span><span title="Required" class="required">Mixed&nbsp;el</span><span class="comma">,&nbsp;</span><span title="Required" class="required">Object/String&nbsp;o</span><span class="comma">,&nbsp;</span><span title="Optional" class="optional">[Boolean&nbsp;returnElement]</span><span class="closeparen">&nbsp;)</span><span class="colon">&nbsp;:&nbsp;</span><span class="return">HTMLElement/Ext.Element</span><div class="mdesc"><div class="short">Creates new DOM element(s) and overwrites the contents of el with them.</div><div class="long">Creates new DOM element(s) and overwrites the contents of el with them.<div class="mdetail-params"><strong>Parameters:</strong><ul><li><code>el</code> : Mixed<div class="sub-desc">The context element</div></li><li><code>o</code> : Object/String<div class="sub-desc">The DOM object spec (and children) or raw HTML blob</div></li><li><code>returnElement</code> : Boolean<div class="sub-desc">(optional) true to return a Ext.Element</div></li></ul><strong>Returns:</strong><ul><li><code>HTMLElement/Ext.Element</code><div class="sub-desc">The new node</div></li></ul></div></div></div></td><td class="msource">DomHelper</td></tr></tbody></table><a id="Ext.DomHelper-events"></a><h2>Public Events</h2><div class="no-members">This class has no public events.</div></div>